login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A278244 Least number with the prime signature of the n-th centered square number (A001844(n)). 2
1, 2, 2, 4, 2, 2, 6, 2, 6, 2, 6, 6, 2, 6, 2, 6, 6, 2, 6, 2, 4, 12, 2, 30, 2, 2, 6, 6, 24, 2, 2, 6, 2, 6, 2, 2, 30, 6, 6, 2, 6, 30, 2, 6, 6, 6, 12, 2, 6, 12, 2, 6, 6, 12, 6, 6, 6, 6, 12, 6, 2, 30, 6, 6, 6, 2, 30, 6, 6, 2, 2, 12, 2, 6, 6, 6, 6, 6, 60, 2, 6, 6, 2, 6, 2, 2, 30, 2, 30, 6, 2, 30, 6, 30, 6, 30, 24, 2, 6, 2, 2, 30, 2, 12, 2, 6, 30, 6, 30, 2, 2, 6, 6, 6, 6 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 0..10000

FORMULA

a(n) = A046523(A001844(n)).

PROG

(PARI)

A046523(n) = my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]) \\ From Charles R Greathouse IV, Aug 17 2011

A001844(n) = 2*((n^2) + n) + 1;

A278244(n) = A046523(A001844(n));

for(n=0, 10000, write("b278244.txt", n, " ", A278244(n)));

(Scheme) (define (A278244 n) (A046523 (A001844 n)))

CROSSREFS

Cf. A001844, A046523.

Cf. also A278162, A278254, A278259.

Sequence in context: A175462 A133946 A286250 * A278542 A033722 A320166

Adjacent sequences:  A278241 A278242 A278243 * A278245 A278246 A278247

KEYWORD

nonn

AUTHOR

Antti Karttunen, Nov 22 2016

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 19 17:35 EDT 2021. Contains 347564 sequences. (Running on oeis4.)